Reenforced flap container



Aug. 3, 1966 J. c. BRACKETT 3,268,149

REENFORCED FLAP CONTAINER Filed June 17, 1964 ZNVENTOR 3 JOHN C.BRACKETT I BY ATTORNEY 3,268,149 Patented August 23, 1966 3,268,149REENFORCED FLAP CONTAINER John C. Brackett, St. Paul, Minn, assignor toWaldorf Paper Products (Iompany, St. Paul, Minn a corporation ofMinnesota Filed June 17, 1964, Ser. No. 375,749 4 Claims. (Cl. 229-37)This invention relates to an improvement in a reenforced flap containerand deals particularly with a container structure in which the innerclosure flaps are supported during the sealing operation.

One of the biggest difficulties which is involved in the sealing ofpaperboard containers, and particularly those used to contain materialwhich is yieldable rather than solid, lies in the fact that the innerclosure flaps tend to fold down into the interior of the containerduring the sealing operation. After the adhesive has been applied to thesealing flaps, it is necessary to apply pressure to the exterior of theflaps in order to produce an effective seal. When this pressure isapplied, the inner flaps have a tendency to fold down into the interiorof the container where the contents of the container are notself-supporting. It is an object of the present invention to provide ameans of supporting the first folded flaps in order to resist the inwardfolding of these flaps when pressure is applied to the later foldedclosing flaps.

A feature of the present invention resides in the provision of acontainer having rectangularly arranged side and end walls, and havingclosure flaps hingedly connected to at least one end of these walls. Inorder to support the first folded flaps from folding inwardly, auxiliaryflaps are cut from the body of the last folded flaps, there auxiliaryflaps being hinged to the wall of the container along the lines of foldof the flaps from which they are cut. These auxiliary flaps arepreferably centrally located between the side edges of the flaps, andare designed to underlie end portions of the first folded flaps whenthey are folded, usually into edge abutting relation. The adhesive isthen applied either to the upper surfaces of the first folded fiaps orthe undersurfaces of the flaps from which the auxiliary flaps have beencut, and the remainder of these latter flaps are then folded down tooverlie the end areas of the first folded flaps to be adhered in facecontact therethrough. Alternatively, the flaps may be pre-coated withadhesive, or stitched in closed condition.

Under usual circumstances, the auxiliary flaps are cut from the flapshinged to the end walls of the container where the containers are notsquare. Where the containers are square, the auxiliary flaps may be cutfrom the center portion of either opposed pair of flaps, in the areathereof adjoining the fold lines connecting these flaps to theirrespective walls.

Rectangular containers are usually closed by folding the flaps connectedto the end walls into a common plane, and then folding the side wallclosing flaps into a common plane and in edge abutting relationoverlying the end wall flaps. When this is done, and sealing pressure isapplied to the flaps, the flaps connected to the end walls have atendency to swing downwardly during the time the pressure is applied. Asa result, the adhesive will set while the superimposed flaps are out offace contact, forming a poor seal. By reversing the sequence of folds,and by providing the auxiliary flaps in the end wall flaps, supports maybe formed by folding these auxiliary flaps inwardly prior to folding theside wall flaps in edge abutting relation, and then folding theremainder of the end wall flaps over the side wall flaps for attachmentthereto.

These and other objects and novel features of the present invention willbe more clearly and fully set forth in the following specification andclaims.

In the drawings forming a part of the specification:

FIGURE 1 is a perspective view of the upper portion of a container withthe various flaps folded outwardly to disclose the construction thereof.

FIGURE 2 is a view similar to FIGURE 1, but showing the auxiliary flapsfolded inwardly to underlie portions of the side wall closing flaps.

FIGURE 3 is a perspective view of the closed and sealed container.

The container A includes a pair of side wall panels 10 and 11 and a pairof end wall panels 12 and 13. The end wall 12 is hingedly connected tothe side wall panels 10 and 11 along parallel fold lines 14 and 15, andthe side wall 11 is connected to the end wall 13 along a parallel foldline 16. The ends of the blank, formed by edges of the side wall 10 andend wall 13 are secured together in any suitable manner such as by thetape 17 to form a collapsible tubular container.

Side wall flaps 19 and 20 are hingedly connected to the upper edges ofthe side walls 10 and 11 along fold lines 21 and 22 respectively, andthe end walls 12 and 13 are connected to the end wall closing flaps 23and 24 respectively along fold lines 25 and 26. The side wall flaps 19and 20 are preferably proper length to fold into edge abutting relationwhen in a common plane, while the end wall flaps 23 and 24 are usuallyof the same length when the container is elongated and terminate inspaced relation when folded into a common plane. The constructiondescribed to this point is conventional.

Auxiliary flaps 27 and 29 are formed within the end walls 23 and 24, andare shown in the drawings as being defined by generally U-shaped cutlines 30 and 31 which terminate at the fold lines 25 and 26 whichconnect the end wall closing flaps to the end walls 12 and 13. Theauxilary flaps 27 and 29 are preferably located intermediate the sideedges of the end Wall closing flaps, and may be individually foldedalong the fold lines 25 and 26 which connect the end wall closing flapsto the end walls. These auxiliary fiaps 27 and 29 form the novel featureof the present invention. In order to function properly, the auxiliaryflaps 27 and 29 are positioned to underlie portions of both of the sidewall closing flaps 19 and 20 along their abutting edges.

In closing the container A, the auxiliary closing flaps 27 and 29 arefirst folded inwardly into a common plane as indicated in dotted outlinein FIGURE 2 of the drawings, and the side wall closing flaps 19 and 20are then folded into a common plane to overlie the flaps 27 and 29 asindicated in the same figure. Adhesive is then applied to the surface ofthe end wall closing flaps 23 and 24 in the area thereof externally ofthe flaps 27 and 29, and these flaps 23 and 24 are then folded into facecontact with the upper surfaces of the side wall closing flaps 19 and20, and then sealing pressure is applied thereto. When in this closedform, the container closure appears as indicated in FIGURE 3 of thedrawings.

The auxiliary closing flaps 27 and 29, being beneath the ends of theside wall closing flaps 19 and 20 assist in preventing the side wallclosing fiaps from folding down wardly when pressure is applied to theflaps 23 and 24. As a result, a greater sealing pressure may be appliedthan is otherwise practical in a container containing material which isnot self-supporting.

During recent years, the use of preapplied adhesive on the closing flapsof containers has increased materially in volume. The adhesive coatedsurface will adhere only The present container 23 and 24 and to theouter surfaces of end portions of the side wall closing flaps 19 and 20in the area thereof which will underlie the end wall closing flaps. Whenapplied in this manner, the containers may be shipped flat as theadhesive coated areas of one blank will not contact the coated surfacesof the adjoining blanks. When the containers are closed in the mannerdescribed, the adhesive coated surfaces of the side wall flaps arepressed against the similarly coated surfaces of the end wall flaps, andthe containers will be tightly sealed.

In accordance with the patent statutes I have described the principlesof construction and operation of my container with supported flaps, andwhile I have endeavored to set forth the best embodiment thereof, Idesire to have it understood that obvious changes may be made within thescope of the following claims without departing from the spirit of myinvention.

I claim:

1. A container flap support for use in a container including:

side and end walls hingedly connected in tubular relation,

side and end wall closure flaps hingedly connected to said side and endwalls and foldable into superimposed relation to form a closure, twoopposed of said closure flaps having auxiliary flaps defined by cutlines terminating at the fold lines connecting said two opposed closureflaps to their -walls,

said auxiliary flaps being independently foldable from the plane of saidtwo opposed flaps from which they are cut,

said auxiliary flaps being folded into a common plane,

the remaining two opposed closure flaps being folded to partiallyoverlie said auxiliary flaps,

said first mentioned two opposed closure flaps being secured inoverlying relation to portions of said remaining two opposed closureflaps.

2. The structure of claim 1 and in which said remaining two opposedclosure flaps are substantially in end abutting relation.

3. The structure of claim 1 and in which said auxiliary flaps arecentrally located between the side edges of said two opposed closureflaps.

said end wall closure flaps being divided into an outer flap portion andan auxiliary flap by -a generally U-shaped cut line in said end wallclosure flaps terminating at the fold lines connecting the same to saidend walls, said outer flap portion and auxiliary flap of each endclosure flap being independently foldable,

said auxiliary flap being positioned, when folded inwardly, to underlieportions of both of said side wall closure flaps when said side wallclosure flaps are folded inwardly, and

said outer flap portions being foldable outwardly of said side wallclosure flaps and into face contact therewith.

4. A container flap support for use in a container including:

side and end walls hingedly connected in tubular relation,

side and end Wall closure flaps hingedly connected to said side and endwalls and foldable into superimposed relation to form a closure,

said end wall closure flaps being divided into an outer flap portion andan auxiliary flap by a generally U-shaped cut line in said end wallclosure flaps terminating at the fold lines connecting the same to saidend walls, said outer flap portion and auxiliary flap of each endclosure flap being independently foldable,

said auxiliary flap being positioned, when folded inwardly, to underlieportions of both of said side wall closure flaps when said side wallclosure flaps are folded inwardly,

said auxiliary flaps being folded into a common plane,

said side wall closure flaps being folded to at least partially overliesaid auxiliary flaps, and

said end wall closure flaps being secured in overlying relation toportions of said side wall closure flaps.

2,693,298 11/1954 Palmer 220118 2,703,197 3/1955 Brasch 22937 GEORGE O.RALSTON, Primary Examiner.

1. A CONTAINER FLAP SUPPORT FOR USE IN A CONTAINER INCLUDING: SIDE ANDEND WALLS HINGEDLY CONNECTED IN TUBULAR RELATION, SIDE AND END WALLCLOSURE FLAPS HINGEDLY CONNECTED TO SAID SIDE AND END WALLS AND FOLDABLEINTO SUPERIMPOSED RELATION TO FORM A CLOSURE TWO OPPOSED OF SAID CLOSUREFLAPS HAVING AUXILIARY FLAPS DEFINED BY CUT LINES TERMINATING AT THEFOLD LINES CONNECTNG SAID TWO OPPOSED CLOSURE FLAPS TO THEIR WALLS, SAIDAUXILIARY FLAPS BEING INDEPENDENTLY FOLDABLE FROM THE PLANE OF SAID TWOOPPOSED FLAPS FROM WHICH THEY ARE CUT, SAID AUXILIARY FLAPS BEING FOLDEDINTO A COMMON PLANE, THE REMAINING TWO OPPOSED CLOSURE FLAPS BEINGFOLDED TO PARTIALLY OVERLIE SAID AUXILIARY FLAPS, SAID FIRST MENTIONEDTWO OPPOSED CLOSURE FLAPS BEING SECURED IN OVERLYING RELATION TOPORTIONS OF SAID REMAINING TWO OPPOSED CLOSURE FLAPS.